Back to 2017 Cadillac ATS

2017 CADILLAC ATS

3.6L V6RWDAUTOMATICgas
2 active safety recalls on this vehicle — view recalls
Repairs0Labor505Torque4895Fluid7DTC969Battery0Maintenance0Recalls2
P3800high severityPowertrain

48V Mild Hybrid System General Malfunction

on 2017 Cadillac ATS 3.6L V6 · RWD

What this code means

The 48V mild hybrid system has detected a general fault preventing normal operation. The belt-driven starter-generator (BSG) and 48V battery are not functioning correctly.

Symptoms

  • Mild hybrid functions disabled
  • Increased fuel consumption
  • No electric boost assist
  • Coasting recuperation disabled
  • Start-stop not functioning
  • Engine feels less responsive

Common causes

  • 48V battery management fault
  • BSG control module error
  • 48V DC-DC converter failure
  • CAN communication error between modules
  • 48V wiring harness damage

Diagnostic steps

  1. Read 48V system fault codes
  2. Check 48V battery voltage and SOC
  3. Test BSG control module communication
  4. Inspect 48V wiring and connectors
  5. Monitor 48V system during engine start and coast

Repair notes

Diagnose and replace failed 48V component. System must be de-energized before service. 48V systems can cause burns and arc flash.

Other Powertrain codes on this vehicle

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